The present invention generally relates to cushions and a method of making seamless support cushions.
A recent surge in the number of wrist and arm occupational injuries, resulting from repetitive computer keyboard use, has prompted the development of countless devices directed at alleviating this modern problem. xe2x80x9cCarpal Tunnel Syndromexe2x80x9d has become a well known term describing a group of symptoms, including tendinitis, and epicondylitis, that occurs as a result of repetitive flexion of the wrist joints. Not only are the symptoms of Carpal Tunnel Syndrome extremely painful, they have the potential to be permanently debilitating. Fortunately, it has been found that if the causes of the disease are minimized or eliminated in time, further damage therefrom may be averted.
Wrist wraps, directed at immobilizing the wrist joint, and wrist supports, directed at propping the hand at a position which minimizes repetitive wrist flexion, have been heretofore developed. These devices are used extensively by data entry personnel and other keyboard operators in order to prevent wrist and arm injuries.
The present invention is directed at an inexpensive method for manufacturing gel and/or foam cushions that may be used as highly effective, comfortable wrist supports. In a broad sense, the method may be used to produce gel or foam cushions for other uses. In addition to providing a soft support gel or foam cushion in accordance with the present invention, it is formable. That is, the cushion can be bent, twisted or contoured to a desired shape to fit the needs of a user. This formation of the cushion by such bending, twisting or the like, is maintained by the cushion, hence the cushion is formable to a desired shape.
Some prior art wrist supports, though designed to minimize repetitive wrist flexion, tend to be uncomfortable to use after a period of time. Notably, because such devices cannot be positioned or oriented for conforming and supporting the underside of a user""s wrist, at a proper angle, flow of blood to the wrist may be impeded. A number of prior art wrist supports utilize foam materials, such as foam rubber. Unfortunately, the resiliency of the foam alone does not provide proper support for the wrist.
Cushioning devices having liquid or gel filled bladders have been developed in the attempt to provide a more comfortable, more durable support for the wrist than is possible with solid or foam rubber supports. For example, U.S. Pat. No. 5,435,508 discloses a wrist rest support comprising a viscous, fluid-filled bladder removably inserted in a machine washable outer covering.
This prior art device, and others which are similar thereto, are manufactured by several independent steps, including sewing or other means of assembling the bladder, filling the bladder with the desired liquid, sealing the bladder such that it will resist leakage, and fashioning an outer covering in which to enclose the liquid filled bladder. However, as is the case with foam only suports, gel only wrist supports also do not provide proper angular wrist supports.
The present invention provides a substantially less complicated process for manufacturing a comfortable fabric covered cushion that includes all the advantages of a liquid support medium. Although the method of the present invention produces a fabric covered gel/foam cushion, no sewing, sealing or gluing is required in the process of making the cushion.
Notably, because a cushion manufactured in accordance with the present invention does not include a fluid filled bladder, there is no possibility that jewelry worn by the operator will rupture the cushion and cause leakage of its contents.
Furthermore, a cushion in accordance with the present invention is seamless due to the unique method of manufacturing same, thus eliminating the possibility of the cushion snagging delicate clothing that may be worn by the keyboard operator.
A cushion made in accordance with the method of the present invention will adhere to any typical surface on which it is placed, for example, a desk top. This eliminates potential frustration suffered by a keyboard operator who must contend with a wrist support that migrates and slips along the desk top due to the natural movement of the operator""s hand and arm. Notably, the cushion requires no additional components to affix, clamp or secure the cushion to a surface. The cushion may be quickly and easily removed, and its position readjusted as desired, for example, when being used by more than one user.
Overall, the present invention provides an inexpensive method of manufacturing a comfortable, durable cushion.
Of most importance, the present invention provides not only all of the desirable features hereinabove enumerated, but also includes the ability of being formed, by a user, to a shape which provides individual comfort for the use. That is, proper angular wrist support.
A formable cushion in accordance with the present invention generally includes a cushion produced by coating one side of a stretchable fabric with gel or foam in order to make the fabric resistant to passage of air therethrough and disposing the coated fabric over a mold adapted for vacuum forming of the coated fabric.
The vacuum is applied between the coated fabric and the mold to cause an imminent contact between another side of the coated fabric and the mold by stretching of the fabric. A first additional volume of gel or foam is deposited on the fabric coating while the vacuum is being applied in order to cause bonding between the first additional volume and the coated fabric. A formable member is then disposed on to the first additional volume of gel or foam and a second additional volume of gel or foam is disposed on the formable member which may be a metal plate.
After the first and second additional volumes of gel or foam are allowed to solidify, the solidified gels or foams with the metal plate therebetween and the coated fabric fixed thereto are removed from the mold in order to obtain a formable cushion.
In an alternative embodiment of the present invention, a formable cushion is produced by disposing a film over a mold adapted for vacuum forming of the film and applying the vacuum between the film and the mold to cause intimate contact between the mold and the film. Thereafter, a first volume of foam/gel is deposited on the film while vacuum is being applied in order to enable the foam/gel to intimately contact the film. A formable sheet is then disposed onto the first volume of foam/gel and thereafter a second volume of foam/gel is disposed over the formable sheet.
After allowing the first and second volumes of the foam/gel to solidify, the solidified foam/gels with the formable sheet therebetween are removed from the mold in order to obtain a formable gel cushion.
In yet another embodiment of the present invention, the film may not be utilized and the foam/gel cushion is produced by depositing a first volume of foam/gel into a mold with the first volume of foam/gel comprising a foam/gel solidifying to a relatively soft compressible layer upon heating thereof. A formable sheet is then disposed onto the first volume of foam/gel and a second volume of foam/gel is deposited onto the formable sheet. The second volume of foam/gel comprises a foam/gel solidified to a relatively firm pliable back layer.
Thereafter, the mold is heated to solidify the first and second volumes foam/gel and the solidified foam/gel is removed from the mold with the formable sheet therebetween in order to obtain the formable cushion.
In yet another embodiment of the present invention, a formable cushion is produced by providing a mold having a first cavity and a second cavity in fluid communication with one another, with the first cavity having a greater depth than the second cavity.
A first volume of foam/gel is deposited into the first and second cavities in an amount providing a level surface of foam/gel.
The level surface of foam/gel is then covered with a formable sheet and a second volume of foam/gel is disposed onto the formable sheet.
Thereafter heat and pressure applied to the first and second volumes of the foam/gel within a mold with the formable sheet providing a barrier to compression of the foam/gel deposit in the first cavity which results in the second volume of foam/gel solidifying to a relatively firm pliable back layer, with the first volume of foam/gel in the second cavity solidifying into a relatively firm pliable front layer, and the first volume of foam/gel in the first cavity solidifies into an integral relatively soft compressible cushion layer.